The present invention relates to release coatings used in cooking and baking foods. The coatings encompassed by the invention comprise a thermosettable polyorganosiloxane resin, a noncurable polydiorganosiloxane fluid, and a combination of at least two compounds which contain different metals. Optionally, the coatings may also include a carboxylic acid.
Siloxane resins and fluid coatings have been known and used as release coatings for a number of years. U.S. Pat. No. 2,606,510 sets forth the use of resins, and U.S. Pat. No. 2,462,242 sets forth the use of fluids. U.S. Pat. No. 2,672,104 teaches hydroxylated polymethylphenylsiloxane resin can be used as a bakeware release coating.
Siloxane resins and fluids have been used in combination as release coatings for a number of years. Such combinations are especially useful because of their ability to release a wide range of foods, and their durability. U.S. Pat. No. 3,002,946 teaches a bakeware release coating comprising 80-98 weight percent thermosettable resin, 1-10 weight percent hydroxyl-endblocked polymethylphenylsiloxane fluid, and 1-19 weight percent nonthermosettable methyl-endblocked polydiorganosiloxane fluid.
A number of improvement patents on the release coating taught in U.S. Pat. No. 3,002,946 have issued. These improvements have been either improved resins, as disclosed in U.S. Pat. No. 3,925,276, or improved fluids, as disclosed in U.S. Pat. No. 4,302,512.
It is an object of this invention to provide a bakeware release coating more durable than previous bakeware release coatings in regards to its release characteristics. It is a further object to provide a coating which is easy to remove, nontoxic and easy to apply to coated and uncoated surfaces.